Step inside this dimly-lit tavern (once a firehouse) in Boston's South End and enter a temple of Japanese discovery. Anticipate a menu that extends far beyond sushi. Rather, chef-owner Tim Cushman unleashes a serpentine exegesis. Unexpected flavors wrangle receptors, so allow time to explore each and every intricate dish as their nuances make o ya a compelling odyssey. Tim's wife Nancy, a sake sommelier, runs the front of the house. Together, this dynamic duo makes you feel as though you are the most important person in the restaurant.